[Fish]

It is useless to note that insects and animals often devour the vulnerable mucous membranes and the softer parts of dead animals such as the genitalia, instead of trying to burrow through the cowhide. It is pointless to note that incisions to a carcass by the teeth of predators or scavengers often resemble knife cuts. It is pointless to note that bloating often leads to skin splitting in straight lines resembling incision and exposing internal organs. It is of no use to point out that there is little or no blood oozing from the wounds because blood settles, the heart does not pump when an animal is dead, and insects devour the blood that does spill out. And it is certainly pointless to describe the experiment done by the Washington County (Arkansas) Sheriff's Department. They placed a dead cow in a field and had observers watch what happened over the next 48 hours. When they reported that bloating led to incision-like tears in the skin and that blowflies and maggots had cleaned out the soft tissue so that the carcass looked exactly like those that had been attributed to aliens or satanic cultists, they were generally ignored by the community of true believers.

http://www.skepdic.com/cattle.html